Water, food and human security

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1 Water, food and human security Jürgen Scheffran Institute of Geography, KlimaCampus, Universität Hamburg Climate and Society Lecture 4, November 20, 2014 p. 1

2 Water, food and human security Questions: How does climate change affect water and food supply? To which degree does it affect human security? Recommended readings: Sections 6.1, 6.2, 6.3 of: WBGU World in Transition Climate Change as a Security Risk, German Advisory Council on Global Change, Berlin: Springer, Background material (optional): Josef Schmidhuber, Francesco N. Tubiello, Global food security under climate change, PNAS, Dec. 11, 2007, 104(50): p. 2

3 Connection between energy and climate impacts Energy in production and consumption CO 2 emissions CO 2 concentration in atmosphere Global mean temperature Natural resources Human security risks Societal stability and conflict p. 3

4 Complex feedbacks and loops in climate-society interaction Natural resources water land ecosystems biodiversity marine resources non-renewables adaptation impact Human security water food energy health income livelihood sustainability stress development adaptive capacity resilience framing response Climate system temperature precipitation extreme weather ice cover ocean currents sea level risk mitigation Societal stability political events migration violence conflict cooperation institutions Source: Scheffran et al, Climate Change and Violent Conflict, Science, 18 May 2012

World map of climate risks Sealevel rise Harvest loss Storms Collapse Amazon forest Glacier retreat Shutdown of thermohaline circulation Sealevel rise Loss of Artic sea ice Floods Droughts Tropical

5 World map of climate risks Sealevel rise Harvest loss Storms Collapse Amazon forest Glacier retreat Shutdown of thermohaline circulation Sealevel rise Loss of Artic sea ice Floods Droughts Tropical Droughts Monsoon Food suppression insecurity Diseases Species loss Species loss Water scarcity Species loss Glacier melt and hydrological cycle Monsoon suppression Food insecurity Sealevel rise Floods & Storms Loss of coral reefs Methane outburst Sealevel rise Loss of species & ecosystems Collapse West Antarctic Ice Sheet p. 5

6 Projected impacts of climate change 0 C Food Global temperature change (relative to pre-industrial) 1 C 2 C 3 C 4 C 5 C Falling crop yields in many areas, particularly developing regions Possible rising yields in some high latitude regions Falling yields in many developed regions Water Ecosystems Small mountain glaciers disappear melt-water supplies threatened in several areas Extensive Damage to Coral Reefs Extreme Weather Events Risk of Abrupt and Major Irreversible Changes Significant fall in water availability e.g. Mediterranean and Southern Africa Rising number of species face extinction Sea level rise threatens major cities Rising intensity of storms, forest fires, droughts, flooding, heat waves Increasing risk of dangerous feedbacks and abrupt, large-scale shifts in the climate system Source: stern p. review 6

7 Vulnerability, risk and adaptation Vulnerability: exposition, sensitivity, adaptive capacity IPCC SREX 2011/12 p. 7

8 Vulnerability and adaptation Impact of climate change on systems, persons or social groups: Impact = Vulnerability x Intensity of climate change Oxford English Dictionary (Oxford 2009): Vulnerability to loss (damage, harm, and hazard). System is vulnerable (from Latin vulnerare to wound ) if it is exposed to being attacked or harmed. Blaikie, Cannon, Davis and Wisner (1994): vulnerability is the characteristics of a person or group in terms of their capacity to anticipate, cope with, resist, and recover from the impact of a natural hazard. Vulnerability depends on the person, the type of event and the actions taken against the hazard. Some persons may be more vulnerable to the same event than others, and some may not be vulnerable at all. Events causing vulnerability may be compensated by responses to protect against it or avoid it in the first place. p. 8

9 Vulnerability and adaptation IPCC (2007): Vulnerability is the degree, to which a system is susceptible to, or unable to cope with, adverse effects of climate change, including climate variability and extremes. Vulnerability is a function of the character, magnitude, and rate of climate change and variation to which a system is exposed, its sensitivity, and its adaptive capacity. Adaptation is the adjustment in natural or human systems in response to actual or expected climatic stimuli or their effects, which moderates harm or exploits beneficial opportunities. Vulnerability = exposure x sensitivity adaptive capacity p. 9

10 Sensitivity Sensitivity: how much the change in one variable is affected by the change of another variable Sensitivity in IPCC (2007): sensitivity in the context of climate change is the degree to which a system is affected, either adversely or beneficially, by climate variability or change. The effect may be direct (e.g., a change in crop yield in response to a change in the mean, range or variability of temperature) or indirect (e.g., damages caused by an increase in the frequency of coastal flooding due to sea-level rise). Climate sensitivity: temperature change induced by a doubling of CO2 concentration in the atmosphere. Highly sensitive responses (overreactions) could affect the structure of a system and thus its stability. p. 10

11 Adaptation and resilience Vulnerability depends on regional adaptive capacity to limit impacts Responses: Adapt to change; protection; damage limitation and disaster management; conflict resolution Resilience: Capacity to resist shocks and surprises and to rebuild Depends on magnitude of change and capacity of the community to resist disturbances, cope with stress and transform livelihood. Strengthen social capability of people in their creative and collective efforts to handle the problems associated with climate change. Build social networks, cultivate diversity, mainten flexibility Critical perspective: those who are not responsible for climate change are supposed to adapt and be resilient p. 11

12 Human security Centered on the security and welfare of human individuals Focuses on shielding people from critical and pervasive threats and empowering them to take charge of their lives (CHS, 2003). Human security is people-centered and thus concerned with how people behave and how their behavior can be influenced in ways that foster or undermine individual and group wellbeing. (UNDP 1994) Broad concept: analytic usefulness? p. 12

13 Conflict constellations as drivers of international destabilization Source: WBGU 2006 p. 13

14 Conflict constellations in climate hotspots Source: WBGU 2007 p. 14

15 Global distribution of the world s water Source: GEO-4 p. 15

16 Change in climatic water balance based on observations in the period ( ) WBGU 2007 Climatic water balance is the result of the difference between precipitation and potential evapotranspiration. p. 16

17 Framework of drivers and responses in freshwater systems p. 17

18 Percentage change of mean annual streamflow for a global mean temperature rise of 2 C above p. 18

19 Human vulnerability to climate change induced decreases of renewable groundwater resources by the 2050s p. 19

20 Indices of water shortages affecting people Per capita water availability (Falkenmark indicator): water stress when water resources are less than 1,000m3 per capita per year. Quotient between water withdrawal and available resources: Water stress when water withdrawal exceeds 40 % of available resources Physical water scarcity: water resources cannot meet the demands of the population. More than 75% of river flows are allocated to agriculture, industries or domestic purposes (accounting for recycling of return flows). Economic water scarcity: lack of investment, poor infrastructure and unequal distribution of water. People s water requirements cannot be adequately met, or marginalized population lacks access to water Ecological water scarcity: withdrawal of water resources for human use is so great that it threatens the integrity of ecosystems, and people who depend on the services of these ecosystems suffer damage. p. 20

21 Average national water footprint per capita A. Y. Hoekstra A. K. Chapagain, 2007 p. 21

22 Regions with physical and economic water stress WBGU 2007, based on IWMI, 2007 p. 22

23 Water availability and withdrawals Source: Vital Signs 2013

24 Changes in global water use by sector Source: UNEP/GRID-Arendal 2002, based on Shiklomanov and UNESCO 1999 Source: GEO-4 p. 24

25 Irrigation Source: Vital Signs 2013 p. 25

26 Source: Vital Signs 2013 p. 26

27 Water stress and climate change Water stress: availability of and access to water; exposure to water-related hazards, such as floods, droughts or ill-health. More than one billion people without access to clean water About a quarter of world population lives in water-stressed areas Increasing population densities, changing patterns of water use and growing economic activities increase water pressures Climate change will alter magnitude and timing of water stress, affects agriculture output (circa 80% of agriculture is rainfed), and worsen water pollution, human health and economic wealth. Dry areas in Sub-Saharan Africa, South Europe, Central China, among others, could experience a shift of climate zones, with increased risks of water shortage, droughts and desertification. Agriculture will compete with urban areas and other business sectors for water supplies. p. 27

1,000m3/capita A1, A2, B1: IPCC/SRES scenarios b) Quotient

28 Projections of populations suffering severe water stress a) Falkenmark indicator: available water amount < 1,000m3/capita A1, A2, B1: IPCC/SRES scenarios b) Quotient between water withdrawal and available amount > 0.4. WBGU 2007 p. 28

29 Water use and water scarcity Relationship between water, security and conflict: continued debate for over two decades Most literature is based on individual case studies to demonstrate conflicting water relationship while cooperation has been largely neglected. Water scarcity undermines human security and heightens competition for water and land resources, undermining living conditions of communities. Uneven water distribution: migration or resource capture in neighbour region Disadvantaged groups could seek to displace another group from water-rich territory or water-rich region could secede from central government control. p. 29

30 Water use: conflict or cooperation? Lack of systematic empirical studies about the link between water and conflict Time series-data (Levy et al 2005): significant correlation between rainfall deviations below normal and the likelihood of conflict. Oregon State University (Transboundary Freshwater Dispute Database): likelihood and intensity of dispute rises as the rate of change within a basin exceeds the capacity to absorb change (Yoffe et al. 2004). Shared freshwater resources: overwhelmingly cooperative, rare violent conflict far outweighed by international water agreements. Greatest water stress in countries without political and institutional framework for crisis management and conflict resolution. Complex causal relationship between hydro-climatology and water-related political relations which depends on socioeconomic conditions and institutional capacity p. 30

31 Climate-induced degradation of freshwater resources Source: WBGU 2006 p. 31

32 Extent of agricultural systems Sources: Re-drawn from Sebastian 2006, derived from FAO and IIASA 2000, Ramankutty 2002, Ramankutty 2005, and Sieber and others 2006 p. 32

33 Arable land Source: GEO-4 p. 33

34 Average corn yields in the United States Source: Troyer, 1990 Troyer, 1990 p. 34

35 Projected US corn yield increases p. 35

36 Grain yield of predominantly rainfed maize Source: Rockström 2009 p. 36

37 Grain yield of predominantly rainfed wheat ( ) Source: Rockström 2009 p. 37

38 World grains Source: Vital Signs 2013 p. 38

39 Meat production and consumption Source: Vital Signs p

40 Marine resources Source: Vital Signs 2013 Source: Vital Signs p

41 What is food security? Food security exists when all people, at all times, have physical, social and economic access to sufficient, safe and nutritious food that meets their dietary needs and food preferences for an active and healthy life. Household food security is the application of this concept to the family level, with individuals within households as the focus of concern. Food insecurity exists when people do not have adequate physical, social or economic access to food as defined above. Undernourishment exists when caloric intake is below the minimum dietary energy requirement (MDER). The MDER is the amount of energy needed for light activity and to maintain a minimum acceptable weight for attained height. It varies by country and from year to year depending on the gender and age structure of the population. The World Food Summit goal is to reduce, between and 2015, the number of undernourished people by half. Millennium Development Goal 1, target 1C, is to halve, between 1990 and 2015, the proportion of people who suffer from hunger. Source: FAO 2010 p. 41

42 Global food production ( ) Source: WBGU 2007 and Le Monde diplomatique, 2007 p. 42

43 Number of undernourished people in the world ( to 2010) FAO 2010 p. 43

44 Proportion of undernourished people in developing countries ( to 2010) FAO 2010 p. 44

45 Share of agriculture in GDP and per capita income (2004) Source: WBGU 2007 p. 45

46 Food price indicators Source: IPCC 2014, WG-2 p. 46

47 Is there a link between riots and the price of food? Death tolls in parentheses p. 47

48 p. 48

49 Singh et al 2009 p. 49

50 Impact of climate change on food security More than 850 million people undernourished, and agricultural areas overexploited in many parts of the world. Climate change will likely reduce crop productivity and worsen malnutrition and food insecurity Significant variations from region to region. Global warming of 2-4 o C decreases agricultural productivity worldwide and reinforced by desertification, soil salinization, and water scarcity (WBGU 2007). Food production severely threatened by global warming in lower latitudes, particularly through loss of cereal harvests and insufficient adaptive capacities (IPCC 2007b). Temperature rise of >4 C with major negative impacts on global agriculture. p. 50

51 Photosynthetic rates of C3 and C4 plants p. 51

52 Percentage simulated yield and local temperature change for major crops Blue: presence Red: absence of simple agronomic adaptation Source: IPCC 2014, WG-2 p. 52

53 Summary of estimates of the impact of recent climate trends on crop yields Source: IPCC 2014, WG-2 p. 53

54 Impact of climate trends on mean crop yield Source: IPCC 2014, WG-2 p. 54

55 Projected changes in crop yields due to climate change over the 21st century Source: IPCC 2014, WG-2 p. 55

56 As temperatures in Southeast Asia rise, agricultural production increases at first, then declines USDA 2001 p. 56

57 Effect of increase in temperature and CO2 on simulated grain yields of irrigated rice with improved N management in different regions of India Source: Singh 2009 p. 57

58 Climate change impacts on crop, livestock & forest production IPCC estimates by 2050 IPCC AR4 WGII p. 58

59 Climate change affects four dimensions of food security Food production and availability: direct changes in agro-ecological conditions and indirect effect on growth and distribution of incomes, and thus demand for agricultural produce. Changes in land suitability, potential yields (e.g. CO2 fertilisation) and production of current cultivars are likely. Stability of food supplies: variable weather conditions, increasing frequency and severity of extreme weather. Greater fluctuation in crop yield and local food supplies can adversely affect food supplies & food security. Climate fluctuations most in semi-arid/sub-humid regions, likely reduce crop yield, livestock numbers & productivity, mostly in poor regions of sub-saharan Africa and South Asia. Access to food: ability of individuals, communities and countries to purchase food in sufficient quantities and quality. Falling real prices for food and rising real incomes over the last 30 years have improved access to food in many developing countries. Possible food price increases and declining rates of income growth resulting from climate change may reverse this trend. Food utilisation: Climate change may initiate a vicious circle where infectious diseases, including water-borne diseases, lead to hunger, which makes the affected population more susceptible to diseases, including declines in labour productivity and increase in poverty, morbidity and mortality. Source: Schmidhuber and Tubiello (2007) p. 59

60 Multiple Exposure: Food insecurity arises from overlapping and interacting stressors 7 12 Misselhorn 2005 Global Environmental Change p. 60

61 Framework of drivers and responses in food security Source: IPCC 2014, WG-2 p. 61

62 Vulnerability of food system to global environmental change Integrated perspective GLOBAL ENVIRONMENTAL CHANGE (GEC) Change in type, frequency & magnitude of environmental threats Capacity to cope with, and adapt to, GEC FOOD SYSTEM RESILIENCE / VULNERABILITY Exposure to GEC SOCIETAL CHANGE Change in institutions, resource accessibility, economic conditions, etc. Adapted from Ingram & Brklacich, 2002; Ericksen, 2008 p. 62

63 Climate-induced decline in food production Source: WBGU 2006 p. 63

64 Water energy food nexus in the context of climate change Source: IPCC 2014, WG2 p. 64

Water and Climate Change. David Coates Secretariat of the Convention on Biological Diversity Montreal Canada

Water and Climate Change. David Coates Secretariat of the Convention on Biological Diversity Montreal Canada Water and Climate Change David Coates Secretariat of the Convention on Biological Diversity Montreal Canada Water and climate change How important is water? What do ecosystems have to do with it? How important